/sqlalchemy-views

Add CreateView and DropView to SQLAlchemy

Primary LanguagePythonOtherNOASSERTION

View Manipulation for SQLAlchemy

Adds CreateView and DropView constructs to SQLAlchemy.

Status

Current version is 0.2.1. Although it was released in 2015, it's based on stable pieces of the SQLAlchemy API, so there has been no maintenance required so far to keep compatibility with new SQLAlchemy or python versions.

As of 2018, this package is still working with latest Python and SQLAlchemy.

Usage

Examples:

>>> from sqlalchemy import Table, MetaData
>>> from sqlalchemy.sql import text
>>> from sqlalchemy_views import CreateView, DropView
>>> view = Table('my_view', MetaData())
>>> definition = text("SELECT * FROM my_table")
>>> create_view = CreateView(view, definition)
>>> print(str(create_view.compile()).strip())
CREATE VIEW my_view AS SELECT * FROM my_table
>>> create_view = CreateView(view, definition, or_replace=True)
>>> print(str(create_view.compile()).strip())
CREATE OR REPLACE VIEW my_view AS SELECT * FROM my_table
>>> drop_view = DropView(view)
>>> print(str(drop_view.compile()).strip())
DROP VIEW my_view
>>> drop_view = DropView(view, if_exists=True, cascade=True)
>>> print(str(drop_view.compile()).strip())
DROP VIEW IF EXISTS my_view CASCADE

Note that the SQLAlchemy Table object is used to represent both tables and views. To introspect a view, create a Table with autoload=True, and then use SQLAlchemy's get_view_definition method to generate the second argument to CreateView.

Installation

sqlalchemy-views is available on PyPI and can be installed via pip

pip install sqlalchemy-views

Limitations

Various SQL dialects have developed custom CREATE VIEW and DROP VIEW syntax. This project aims to provide the core set of functionality shared by most database engines.

Acknowledgements

Some design ideas taken from the SQLAlchemy Usage Recipe for views.

Package structure is based on python-project-template.